Introduction: Allergic contact dermatitis (ACD) is a common cutaneous inflammatory skin disorder that is diagnosed via epicutaneous patch testing (PT). ACD may also coexist with other systemic inflammatory conditions such as atopic dermatitis and psoriasis. Many of the treatments used to manage severe ACD, along with other systemic conditions, interact with and suppress the immune system, thereby potentially interfering with the mechanism of PT. There is uncertainty in the literature regarding the effects of immunosuppression on the results of PT.
Methods: A comprehensive literature review was conducted using PubMed and Google Scholar to identify articles relevant to the topic of this review. Only articles available in English were included.
Areas covered: This review discusses the impact of immunomodulating therapies on the results of PT. We summarize the available evidence and provide updated recommendations for several immunomodulating drugs commonly used in patients undergoing PT.
Expert opinion: In general, the results of PT are most reliable when performed without immunosuppression. If this is not feasible, it is best to have patients on as low a dose of immunosuppression as possible, but it may not be necessary to stop or change an immunomodulating drug prior to PT.
Keywords: Allergic contact dermatitis; biologics; contact sensitization; dupilumab; immunosuppression; patch testing.